Not Applicable.
Not Applicable.
1. Field of the Invention
The present invention is directed generally to a structure having thin films that does not exhibit spotting and non-wetting characteristics and, more particularly, to a structure having thin films that may include an adhesion layer.
2. Description of the Background
Films used in integrated circuits are becoming thinner as minimum feature sizes decrease and as the competitive nature of integrated circuit fabrication forces manufactures to produce smaller parts (i.e. die) in order to produce smaller and less expensive integrated circuits.
A result of decreasing film thickness is that some materials will not form a conformal film below certain thicknesses. Instead, those materials exhibit xe2x80x9cspottingxe2x80x9d or xe2x80x9cnon-wettingxe2x80x9d characteristics whereby the material forms xe2x80x9cislandsxe2x80x9d separated by gaps where the material will not form. One example of such a material is platinum, which exhibits spotting when formed on silicon at a thickness less than about six hundred (600) Angstroms and then annealed to 700xc2x0 C.
Platinum, as well as other materials, is important when forming integrated circuits because it exhibits desirable characteristics during fabrication steps. For example, platinum does not readily form an oxide during annealing in oxygen.
Therefore, the need exists for a structure having thin films that does not exhibit spotting or non-wetting characteristics.
The present invention is directed to a conductive structure including an adhesion layer and a conductor in contact with the adhesion layer and having a thickness of less than six hundred Angstroms. The present invention may be used to form devices, such as capacitors. A capacitor constructed according to the present invention includes an adhesion layer, a conductor in contact with the adhesion layer and having a thickness of less than six hundred Angstroms, a second conductor, and a dielectric between the first and second conductors.
The present invention is also directed towards structures wherein iridium or rhodium may be used in place of the combination of the adhesion layer and conductor.
The present invention solves problems experienced with the prior art because it allows for the formation of thin films, such as platinum, without wetting effects. Those and other advantages and benefits of the present invention will become apparent from the description of the preferred embodiments hereinbelow.